U.S. patent number 7,129,727 [Application Number 11/258,041] was granted by the patent office on 2006-10-31 for defect inspecting apparatus.
This patent grant is currently assigned to Hitachi High-Technologies Corporation. Invention is credited to Eiichi Hazaki, Yoshikazu Inada, Yasuhiko Nara, Yoshinori Numata, Tsutomu Saito, Hirofumi Sato, Osamu Yamada.
United States Patent |
7,129,727 |
Saito , et al. |
October 31, 2006 |
Defect inspecting apparatus
Abstract
A defect inspecting apparatus in which a plurality of probes to
measure electric characteristics of a sample including a fine
wiring pattern are combined with a charged-particle beam unit
includes graphic user interfaces (GUI) to simply control the plural
probes. The apparatus includes a probe image processing unit to
display the plural probes on a display; a selecting unit to select,
from the probes displayed on the display, a probe to be operated;
and a display unit to simultaneously display the probe selecting
unit and information indicating that the selected probe is an
operable probe, or the probe is in a non-selected state.
Inventors: |
Saito; Tsutomu (Hitachinaka,
JP), Yamada; Osamu (Hitachinaka, JP),
Hazaki; Eiichi (Tsuchiura, JP), Nara; Yasuhiko
(Hitachinaka, JP), Sato; Hirofumi (Naka,
JP), Inada; Yoshikazu (Toride, JP), Numata;
Yoshinori (Hitachinaka, JP) |
Assignee: |
Hitachi High-Technologies
Corporation (Tokyo, JP)
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Family
ID: |
36205659 |
Appl.
No.: |
11/258,041 |
Filed: |
October 26, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060087330 A1 |
Apr 27, 2006 |
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Foreign Application Priority Data
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Oct 27, 2004 [JP] |
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2004-311865 |
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Current U.S.
Class: |
324/754.03;
324/762.01; 324/754.21; 324/757.01 |
Current CPC
Class: |
G01R
31/307 (20130101); G01R 31/2891 (20130101) |
Current International
Class: |
G01R
31/02 (20060101); G01R 31/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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9-326425 |
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Dec 1997 |
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JP |
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2000-147070 |
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May 2000 |
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JP |
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2002-523784 |
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Jul 2002 |
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JP |
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WO 00/13030 |
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Mar 2000 |
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WO |
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Primary Examiner: Hollington; Jermele
Attorney, Agent or Firm: McDermott Will & Emery LLP
Claims
The invention claimed is:
1. A defect inspecting apparatus, comprising: a charged-particle
source; an emitting unit that emits a charged-particle beam from
the charged-particle source onto a sample; an image shift unit that
moves a point on the sample of the charged-particle beam, the beam
being emitted onto the point; an image obtaining unit that detects
a beam of secondary charged particles appearing due to the
charged-particle beam emitted onto the sample and for obtaining an
image of the sample; a display unit that displays the image
obtained in the preceding step; a storage unit having stored
information about the sample; an image processing unit that
executes image processing on the image to display the image; an
electrooptical unit including a communication unit to connect the
storage unit to the image processing unit; a sample stage that
mounts the sample thereon; a sample chamber including the sample
stage therein; a sample change chamber connected to the sample
chamber to temporarily keep the sample therein; a first
transporting unit that transports the sample between the sample
change chamber and the sample chamber; a probe holder including a
plurality of probes which are brought into contact with the sample
to measure electric characteristics of the sample; a plurality of
probe units that moves the probe holder; a probe holder change
chamber that temporarily keeps the probe holder therein; a second
transporting unit connected to the sample chamber for transporting
the probe holder between the probe holder change chamber and the
sample chamber; a base stage that transports the sample and the
probe units to a position at which the sample and each of the probe
units can be changed; a probe image processing unit that displays
the plural probes on the display unit; a probe selecting unit that
selects, from the plural probes displayed on the display unit, a
probe to be operated; and a probe display unit that simultaneously
displays thereon that the probe selected by the probe selecting
unit is a probe which can be operated and that the probe is a probe
in a non-selection state in which the probe is not selected.
2. A defect inspecting apparatus according to claim 1, further
comprising a probe driving unit that moves the probe holder,
wherein the sample stage, the probe holder, and the probe driving
unit are mounted on the base stage to thereby move the sample and
the probes in an independent manner and at the same time.
3. A defect inspecting apparatus according to claim 1, wherein: an
image obtained by the image processing unit and the plural images
of probes are displayed on the display unit by the probe image
processing unit at the same time; and a probe to be moved toward or
retracted from the image obtained by the image processing unit is
selected from the plural probes by the probe selecting unit.
4. A defect inspecting apparatus according to claim 1, further
comprising a sample information image processing unit that displays
information of the sample as an image on the display unit, wherein:
the image of the information of the sample and the plural images of
probes are displayed on the display unit by the probe image
processing unit at the same time; and a probe to be moved toward or
retracted from the image of the information of the sample is
selected from the plural probes by the probe selecting unit.
5. A defect inspecting apparatus according to claim 3, further
comprising: a target setting unit that sets a target to a desired
position of the sample information image; and a probe contact unit
that brings the probe selected by the probe selecting unit into
contact with the target.
6. A defect inspecting apparatus according to claim 4, further
comprising: a distance calculating unit that calculates, in the
operation to bring the probe into contact with the target, distance
between a tip end of the probe and the target before the probe is
brought into contact with the target; and a distance display unit
that displays the distance calculated by the distance calculating
unit on the display unit.
7. A defect inspecting apparatus according to claim 1, further
comprising: a sample information image processing unit that
displays information of the sample as an image on the display unit,
wherein the obtained image obtained by the image obtaining unit and
the image of the information of the sample are displayed on the
display unit in an overlapped manner.
8. A defect inspecting apparatus according to claim 1, further
comprising: a first retracting unit that retracts, for each of
coordinate axes of the probe unit, the probe unit to a position of
an origin the coordinate axis; a second retracting unit that
retracts the probe unit to a position of an origin of each of
coordinate axes of the probe unit; and a third retracting unit that
retracts a plurality of probe units to positions of origins of
coordinate axes respectively of the probe units, wherein a switch
to operate the first, second, and third retracting units on the
display screen.
9. A defect inspecting apparatus according to claim 1, further
comprising a display rotating unit that rotates a display image on
the display unit displaying the plural probes and the selected
probes selected by the probe selecting unit.
10. A defect inspecting apparatus according to claim 1, further
comprising a selected probe display unit that controls the display
unit so as to display the probe selecting unit.
11. A defect inspecting apparatus, comprising: an emitting module
that emits a charged-particle beam from a charged-particle source
onto a sample; an image shift module that moves a point on the
sample of the charged-particle beam, the beam being emitted onto
the point; a detecting module that detects a beam of secondary
charged particles appearing due to emission of the charged-particle
beam onto the sample; an image creating module that generates an
image associated with the sample according to the secondary
charged-particle beam detected by the detecting unit; a plurality
of movable probes which can make contact with the sample; a probe
selecting module that selects, from the plural probes, a probe to
be brought into contact with the sample; and a display screen that
displays the image which is associated with the sample and which is
created by the image creating module, and the image associated with
the probe selected by the probe selecting unit and the other of the
plurality of movable probes together with information indicating
that the probe selected by the probe selecting unit is displayed
separately from the other of the plurality of movable probes.
12. The defect inspecting apparatus according to claim 11, further
comprising a probe driving module that moves a probe selected by
the probe selecting module in such a manner that the probe and the
sample independently move at the same time.
13. The defect inspecting apparatus according to claim 11, wherein:
an image obtained by the image creating module and the plural
images of probes are displayed on the display screen by the probe
image creating module at the same time; and a probe to be moved
toward or retracted from the image obtained by the image creating
module is selected from the plural probes by the probe selecting
module.
14. The defect inspecting apparatus according to claim 11, further
comprising a sample information image processing module that
displays information of the sample as an image on the display unit,
wherein: the image of the information of the sample and the plural
images of probes are displayed on the display screen by the probe
image creating module at the same time; and a probe to be moved
toward or retracted from the image of the information of the sample
is selected from the plural probes by the probe selecting
module.
15. The defect inspecting apparatus according to claim 13, further
comprising: a target setting module that sets a target to a desired
position of the sample information image; and a probe contact
module that brings the probe selected by the probe selecting module
into contact with the target.
16. A defect inspecting apparatus, comprising: an emitting module
that emits a charged-particle beam from a charged-particle source
onto a sample; an image shift module that moves a point on the
sample of the charged-particle beam, the beam being emitted onto
the point; a detecting module that detects a beam of secondary
charged particles appearing due to emission of the charged-particle
beam onto the sample; an image creating module that generates an
image associated with the sample according to the secondary
charged-particle beam detected by the detecting unit; a plurality
of movable probes which can make contact with the sample; a probe
selecting module that selects, from the plural probes, a probe to
be brought into contact with the sample; and a display screen that
displays the image which is associated with the sample and which is
created by the image creating module, and the image associated with
the probe selected by the probe selecting unit together with
information indicating that the probe selected by the probe
selecting unit is operable; further comprising a sample information
image processing module that displays information of the sample as
an image on the display unit, wherein: the image of the information
of the sample and the plural images of probes are displayed on the
display screen by the probe image creating module at the same time;
and a probe to be moved toward or retracted from the image of the
information of the sample is selected from the plural probes by the
probe selecting module; and a distance calculating module that
calculates, in the operation to bring the probe into contact with
the target, distance between a tip end of the probe and the target
before the probe is brought into contact with the target; and a
distance display screen that displays the distance calculated by
the distance calculating module on the display screen.
17. The defect inspecting apparatus according to claim 11, further
comprising: a sample information image processing module that
displays information of the sample as an image on the display
screen, wherein the obtained image obtained by both the image
creating and the image of the information of the sample are
displayed on the display unit in an overlapped manner.
18. A defect inspecting apparatus, comprising: an emitting module
that emits a charged-particle beam from a charged-particle source
onto a sample; an image shift module that moves a point on the
sample of the charged-particle beam, the beam being emitted onto
the point; a detecting module that detects a beam of secondary
charged particles appearing due to emission of the charged-particle
beam onto the sample; an image creating module that generates an
image associated with the sample according to the secondary
charged-particle beam detected by the detecting unit; a plurality
of movable probes which can make contact with the sample; a probe
selecting module that selects, from the plural probes, a probe to
be brought into contact with the sample; and a display screen that
displays the image which is associated with the sample and which is
created by the image creating module, and the image associated with
the probe selected by the probe selecting unit together with
information indicating that the probe selected by the probe
selecting unit is operable; further comprising: a first retracting
unit that retracts, for each of coordinate axes of a probe selected
by the probe selecting module to a position of an origin the
coordinate axis; a second retracting unit that retracts the probe
to a position of an origin of each of coordinate axes of the probe;
and a third retracting unit that retracts a plurality of probes to
positions of origins of coordinate axes respectively of each of the
probes, wherein a switch to operate the first, second, and third
retracting units on the display screen.
19. The defect inspecting apparatus according to claim 11, further
comprising a display rotating unit that rotates a display image on
the display screen displaying the plural probes and the selected
probes selected by the probe selecting module.
20. The defect inspecting apparatus according to claim 11, further
comprising a selected probe display module that controls the
display screen so as to display the probe selecting module.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a defect inspecting apparatus for
measuring electric characteristics of an electronic element such as
a semiconductor chip by use of a fine probe, and in particular, to
a defect inspecting apparatus using particularly a charged-particle
beam unit for measuring electric characteristics of an electronic
element by bringing the probe into direct contact with the
electronic element.
To inspect electric defects of a complicated electronic circuit
formed on a semiconductor chip, there have been used defect
inspecting apparatuses such as an Electron Beam (EB) tester and a
prober unit. The EB tester inspects an electrically defective point
of a Large-Scale Integrated (LSI) circuit as below. When the tester
emits an electron beam onto a measuring point, secondary electrons
are emitted from the measuring point. The amount of such emitted
secondary electrons varies depending on a voltage value at the
point to thereby detect an electrically defective point of the LSI
circuit. In the prober unit, a plurality of probe needles disposed
according to positions of characteristic measuring pads of an LSI
circuit or mechanical probes are brought into contact with the
measuring pads and/or plugs to measure electric characteristics of
the LSI circuit. When such EB tester or prober unit is employed for
the defect inspection, an operator or a user of the apparatus
confirms a contact position of each probe through a manual
operation while viewing an image of wiring produced by an optical
microscope or a Scanning Electron Microscopy (SEM) image generated
by a Scanning Electron Microscope (SEM).
Since the circuit pattern formed on a semiconductor element such as
an LSI device has been complicated these days, it becomes difficult
to quickly move a probe to an optimal position. To overcome the
difficulty, there exists a technique called Computer Aided Design
(CAD) navigation to reduce the period of time required for moving
the probing. That is, in the inspection of a semiconductor device,
a wiring layout of the device is displayed in association with an
actual image at desired positions on the device, the image being
viewed by the operator for the inspection.
To observe the SEM image, a scanning electronic microscope is
employed to scan a sample using a primary electron beam to produce
a scanned image of a fine pattern sample of a semiconductor. Such
apparatus to observe a fine pattern sample includes an image shift
function to correctly move an emission area of the primary electron
beam or an observing field thereof to an observing point on the
sample by use of a deflector including electrically two stages. The
deflector electrically deflects the primary electron beam in a
range from several micrometers (.mu.m) to about ten .mu.m.
JP-A-2000-147070 describes a probing device including a display
section to display a probe information screen indicating
information to make a probe achieve a desired operation. The
probing device also includes a function to display a sample and the
probe in the probe information screen of the display section, to
present on the display section a probe operation screen area to
move the probe thereto, and to move the probe by a probe controller
in response to an operation signal of the probe operation screen
area. The probing device further includes a function in which when
the operator respectively designates a current position of a tip
end of the probe displayed in the probe information screen and a
moving target position of the tip end in the probe information
screen, the device calculates a moving length or distance from the
current position to the target position and makes the probe
controller according to the moving distance to move the probe to
the target position. The probing device also includes a function to
select one of plural probes.
JP-A-9-326425 describes a defect inspecting apparatus including a
vacuum chamber, a probing needle and a probing needle moving
mechanism to move the probing needle which are disposed in the
vacuum chamber, a sample stand to mount a sample thereon, a charged
particle source, an emitting unit to emit a charged-particle beam
from the charged particle source, a detector to detect charged
particles from the sample, a unit to apply a voltage between the
probing needle and the sample and/or between the probing needles,
and a unit to measure electric characteristics of the sample.
JP-A-2002-523784 describes a probe station to deliver an electric
test signal to an integrated circuit as an object to be
inspected.
SUMMARY OF THE INVENTION
In recent years, the circuit pattern formed on a semiconductor
device such as an LSI device is complex, and the wiring pattern
drawn on a semiconductor wafer and positioning or aligning accuracy
to bring a tip end of a probe into contact with the wafer are in an
order of magnitude of nanometers (nm). In the present stage of art,
it is difficult to automatically conduct the alignment of the probe
needle with such high accuracy, and hence the operation to bring a
tip end of a probe into contact with the wafer is required to be
manually conducted. The number of probes necessary for the defect
inspection is increasing to reproduce operation of circuits on the
semiconductor device. Therefore, the operation of the defect
inspecting apparatus using probes is complicated, and it is
difficult to move probes to optimal probing positions in a short
period of time. Remarkable development and spread of semiconductors
today requires increase in the developing speed of new products. To
increase yield in the production, it is also required to conduct
the defect inspection at a high speed. This results in increase in
load imposed on the user of the defect inspecting apparatus to lead
contact between probes and a sample. That is, when the number of
probes becomes larger, the number of operations to change the
magnification ratio in the probe confirmation screen increases in
the operation to lead contact between probes and the sample, and
for each change of the magnification ratio, it is required that
probes are moved to be within a visual field of the screen. There
arises a problem that to easily operate the probing device, the
user is required to fully become proficient in the operation
procedure of the probing unit. To mitigate the load imposed on the
user, there has been proposed a probing device in which the user
can easily conduct operation to lead the contact between probes and
the sample regardless of his or her dexterity and proficiency.
However, it cannot be considered that the probing device of the
prior art has a device configuration sufficiently mitigating the
load imposed on the user.
It is therefore an object of the present invention that the user
can easily operate probes in a short period of time in
consideration of safety with respect to samples and probes.
The present invention relates to favorably displaying, in a probe
operation screen area, an operation environment and a function
which are required to lead contact between probes and targets on a
sample.
According to the present invention, there is provided a defect
inspecting apparatus including a charged-particle source, an
emitting unit for emitting a charged-particle beam from the
charged-particle source onto a sample, an image shift unit for
moving a point on the sample of the charged-particle beam, the beam
being emitted onto the point, an image obtaining unit for detecting
a beam of secondary charged particles appearing due to the
charged-particle beam emitted onto the sample and for obtaining an
image of the sample, a display unit for displaying thereon the
image obtained in the preceding step, a storage unit having stored
information about the sample, an image processing unit for
executing image processing on the image to display the image, an
electrooptical unit including a communication unit to connect the
storage unit to the image processing unit, a sample stage for
mounting the sample thereon, a sample chamber including the sample
stage therein, a sample change chamber connected to the sample
chamber to temporarily keep the sample therein, a first
transporting unit for transporting the sample between the sample
change chamber and the sample chamber, a probe holder including a
plurality of probes which are brought into contact with the sample
to measure electric characteristics of the sample, a plurality of
probe units for moving the probe holder, a probe holder change
chamber for temporarily keeping the probe holder therein, a second
transporting unit connected to the sample chamber for transporting
the probe holder between the probe holder change chamber and the
sample chamber, a base stage for transporting the sample and the
probe units to a position at which the sample and each of the probe
units can be changed, a probe image processing unit for displaying
the plural probes on the display unit, a probe selecting unit for
selecting, from the plural probes displayed on the display unit, a
probe to be operated, and a probe display unit for simultaneously
displaying thereon that the probe selected by the probe selecting
unit is a probe which can be operated and that the probe is a probe
in a non-selection state in which the probe is not selected.
The defect inspecting apparatus favorably includes a probe driving
unit for moving the probe holder. The sample stage, the probe
holder, and the probe driving unit are mounted on the base stage to
thereby move the sample and the probes in an independent manner and
at the same time.
Favorably, the present invention relates to an apparatus including
a plurality of probes for measuring electric characteristics of a
sample having a fine circuit wiring pattern formed on a
semiconductor wafer and fundamentally relates to a defect
inspecting apparatus including a display section for displaying a
probe information screen to make probes conduct desired operations
according to necessity. The apparatus is configured to include
functions as below. The probe information screen displays a sample
and probes, a probe operation screen area to move probes, and a
charged-particle beam operation screen area to control a
charged-particle beam. There is provided a function in which a
probe control section moves probes in response to an operation
signal in the probe operation screen area. The defect inspecting
apparatus includes a unit to display contours of probes in a
controllable state in the probe information screen, a unit to make
the probe display follow a rotation of the display screen by a
rotation function, and a unit to magnify or minimize, in response
to a change in the display magnification ratio of an electrooptical
system, the contours of the probe display according to the display
magnification ratio. The apparatus also includes a function which
enables, even when controllable probes are absent from the probe
information screen, the user to visually determine size of each of
the probes and an entering direction of the probe to enter the
probe information screen.
The user who operates the defect inspecting apparatus can easily
operate probes in a short period of time only by conducting
operation in the probe operation screen area. There can also be
provided a defect inspecting apparatus in which the user can easily
operate probes in a short period of time in consideration of safety
with respect to samples and probes.
In a defect inspecting apparatus in which probes are combined with
a charged-particle beam device, availability and operability of the
apparatus for the user is remarkably improved.
A defect inspecting apparatus according to the present invention
includes a charged-particle source, an emitting unit for emitting a
charged-particle beam from the charged-particle source onto a
sample, an image shift unit for moving a point on the sample of the
charged-particle beam, the beam being emitted onto the point, an
image obtaining unit for detecting a beam of secondary charged
particles appearing due to the charged-particle beam emitted onto
the sample and for obtaining an image of the sample, a display unit
for displaying thereon the image obtained in the preceding step, a
storage unit having stored information about the sample, an image
processing unit for executing image processing on the image to
display the image, an electrooptical unit including a communication
unit to connect the storage unit to the image processing unit, a
sample stage for mounting the sample thereon, a sample chamber
including the sample stage therein, a sample change chamber
connected to the sample chamber to temporarily keep the sample
therein, a first transporting unit for transporting the sample
between the sample change chamber and the sample chamber, a probe
holder including a plurality of probes which are brought into
contact with the sample to measure electric characteristics of the
sample, a plurality of probe units for moving the probe holder, a
probe holder change chamber for temporarily keeping the probe
holder therein, a second transporting unit connected to the sample
chamber for transporting the probe holder between the probe holder
change chamber and the sample chamber, and a base stage for
transporting the sample and the probe units to a position at which
the sample and each of the probe units can be changed.
The defect inspection apparatus further includes a probe image
processing unit for displaying the plural probes on the display
unit and a sample information image processing unit for displaying
on the display unit an image of information of the sample.
The defect inspection apparatus further includes a probe selecting
unit for selecting, from the plural probes displayed on the display
unit, a probe to be operated, and a probe display unit for
simultaneously displaying thereon that the probe selected by the
probe selecting unit is a probe which can be operated and that the
probe is a probe in a non-selection state in which the probe is not
selected.
In the defect inspecting apparatus, an image obtained by the image
processing unit and the plural images of probes are displayed on
the display unit by the probe image processing unit at the same
time, and a probe to be moved toward or retracted from the image
obtained by the image processing unit is selected from the plural
probes by the probe selecting unit.
The defect inspecting apparatus further includes a sample
information image processing unit for displaying information of the
sample as an image on the display unit. The image of the
information of the sample and the plural images of probes are
displayed on the display unit by the probe image processing unit at
the same time. A probe to be moved toward or retracted from the
image of the information of the sample is selected from the plural
probes by the probe selecting unit.
The defect inspecting apparatus displays the obtained image and the
image of the information of the sample on the display unit in an
overlapped manner.
The defect inspecting apparatus further includes a display rotating
unit for rotating a display image on the display unit displaying
the plural probes and the selected probes selected by the probe
selecting unit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross-sectional view partially showing a
configuration example of a defect inspecting apparatus of the
present invention.
FIG. 2 shows a diagram showing a Graphic User Interface (GUI) of an
SEM control Personal Computer (PC) of the defect inspecting
apparatus.
FIGS. 3A 3D show diagrams respectively showing a probe display GUI
of the SEM control PC of the defect inspecting apparatus.
FIG. 4 shows a probe control GUI of the SEM control PC of the
defect inspecting apparatus.
FIG. 5 shows a GUI for a probe stage change of the SEM control PC
of the defect inspecting apparatus.
FIG. 6 shows a GUI for a base stage change of the SEM control PC of
the defect inspecting apparatus.
FIG. 7 shows a probe display GUI of the SEM control PC of the
defect inspecting apparatus.
FIG. 8 shows a position information storage GUI of the SEM control
PC of the defect inspecting apparatus.
FIGS. 9A 9C show a diagram respectively showing a CAD navigation
function GUI of the SEM control PC of the defect inspecting
apparatus.
FIG. 10 shows a probe unit retraction GUI of the SEM control PC of
the defect inspecting apparatus.
FIG. 11 shows a sample stage control GUI of the SEM control PC of
the defect inspecting apparatus.
FIGS. 12A 12C show a probe automatic contact control GUI of the SEM
control PC of the defect inspecting apparatus.
DESCRIPTION OF THE EMBODIMENTS
Description will now be given of an embodiment by referring to the
drawings. FIG. 1 shows an example of a configuration of a defect
inspecting apparatus as an embodiment of the present invention.
A numeral 101 indicates an element of an SEM electronic optical
system forming a light emitting optical system to emit a primary
electron beam 103 onto a sample to scan the sample with the beam
103. That is, an electron gun 101 of the embodiment indicates a
system including substantially all constituent components required
for an SEM such as an electron source to generated an electron
beam, a deflecting unit to conduct the scanning, and a lens to
focus the electron beam. A numeral 102 is a vacuum chamber
partition wall to separate an atmospheric area from a vacuum area.
Operation of the element 101, specifically, an electron beam
drawing voltage of the electron source, currents to the deflecting
unit and the lens and the like are controlled by an electrooptical
system control unit 116.
As a result of emission of the primary electron beam 103 onto an
inspection sample (sample), a secondary electron beam 105 generated
from the sample is detected by a secondary electron detector 104.
Although a sensor section of the detector 104 is installed within
the vacuum chamber partition wall 102, a fundamental section of the
sensor section to which, for example, wiring to connect a power
source is connected is projected into a space outside the partition
wall. A numeral 106 indicates mechanical probes (probes) to be
brought into contact with a predetermined area of the sample, and
the probes are held by an attachment as a probe holder. A numeral
108 is a probe driving unit to move the probe attachment 107 to a
desired position, specifically, to move the attachment 107 on which
probes 106 are attached to the desired position.
The sample as an actual object of the defect inspection is held on
a sample stand 109. The stand 109 is further held by a sample stand
driving unit 110. The stand 109 and the unit 110 are collectively
called a sample stage. The sample stage and the probe driving unit
108 are configured on a main stage 111. The main stage 111 includes
a driving unit in X and Y directions (in a plane) and a driving
unit in Z (perpendicular) direction to drive the sample stage and
the probe driving unit 108 as a single unit. In this way, the
sample stage and the probe driving unit 108 are configured in a
single unit on the main stage 11 in the embodiment. The defect
inspecting apparatus is configured to move the sample 118 and the
mechanical probes 106 in an independent fashion and as one unit at
the same time. The main stage 111 is further arranged on a base
112.
The sample stand 109 and the attachment 107 are connected to an
electric characteristic measuring unit 113. The measuring unit 113
primarily measures a current-voltage characteristic detected by the
mechanical probes 106 to calculate a desired characteristic value
using the current-voltage characteristic. The desired
characteristic value is, for example, a value of resistance, a
current, or a voltage at a contact position of an associated
mechanical probe 6. To analyze a semiconductor wafer, the measuring
unit 113 is, for example, a semiconductor parameter analyzer. The
reason to connect the unit 113 to the sample stand 109 is that a
power feeding plug is disposed, depending on cases, on a surface of
the sample stand 109 on which the sample is mounted.
The characteristic value measured by the measuring unit 113 is sent
via a transmission line to a control computer 114. The computer 114
conducts a higher-level analysis using the information of the
characteristic value. For example, the computer 114 analyzes the
value to determine whether or not the measuring position is normal.
For the computer 114, a storage unit such as an optical disk, a
hard disk, or a memory is disposed to store the electric
characteristic measured by the measuring unit 113. The computer 114
also controls the overall operation of the defect inspecting
apparatus. For example, the computer 114 controls operations of
constituent components such as the electron gun controller
(electrooptical control unit) 116, the secondary electron detector
104, the probe driving unit 108, and the main stage 111 with a
sample unit.
For this purpose, the control computer 114 includes a memory 115 to
store software to control constituent components connected thereto
and an input unit for the user to input setting parameters for to
set associated devices. The input unit includes, for example, a
keyboard and a mouse to move a pointer on a screen for desired
operation. Data of a wiring layout of a sample to be inspected (to
be referred to as CAD image data) is stored in a CAD workstation
(WS) 117. The workstation includes an image display unit to display
the wiring layout. The workstation is connected to the computer 114
to deliver the CAD image data to the computer 114 according to
necessity. A numeral 118 indicates an inspection sample to be
inspected.
An SEM control PC 119 conducts, in response to a PC or WS GUI
operation or a command input, operations to control SEM items such
as an optical condition, a magnification ratio, a focus, an image
shift, brightness of an SEM image, a scan speed, alignment,
recording of an image, and movement of a stage/probe. A control
panel 120 conducts part of the function of the SEM control PC 119
by operating the mechanical probes 106, the sample unit, and the
main stage 111 using a joystick, a button, or the like. For the
personal computer 119, a workstation may be naturally employed.
Referring next to FIG. 2, description will be given of an example
of GUI displayed on the PC 119 of the defect inspecting apparatus
of FIG. 1, namely, on the SEM.cndot.probe.cndot.stage control PC
119. An SEM.cndot.probe.cndot.stage control GUI 201 mainly includes
eleven fields. An SEM control GUI field 202 includes, to control an
SEM image displayed on an SEM image/CAD data display field 203,
icons and menus to set an SEM optical condition, an SEM
magnification ratio, a focus, an image shift, brightness of an SEM
image, a scan speed, alignment, recording of an image, and the
like. A base stage/DUT (Device Under Test) stage/image shift
control selection GUI 204 includes icons to select either one of a
base stage, a DUT stage, and an image shift to move the item thus
selected and an icon to lock either one thereof such that the item
thus selected is not moved. A base stage control GUI field 205
includes icons to move the main stage 111 to a central position, a
charge-coupled device (CCD) observing position, and a mechanical
probe change position; an icon to remove backlash, and a coordinate
input.cndot.display box. A DUT stage/image shift control GUI field
206 includes, for example, a cross cursor to indicate a moving
position, an arrow icon, a combo box to select a moving length, a
coordinate input.cndot.display box, and a reset button to return
control to an image shift central point. A coordinate memory
display GUI field 207 includes icons to register coordinates of the
main stage, the sample stage, and the image shift; a combo box to
select/call registered coordinates, and a registered coordinates
display box. A probe selection GUI field 208 includes icons to
display "selection or nonselection" and "display or nondisplay" for
a probe unit desired to be driven. A probe retraction control GUI
209 includes an icon to retract all probes. A probe control GUI
field 210 to control driving of the mechanical probes 106 includes
a scroll bar and an arrow icon to control driving of the probe in
the X, Y, and Z directions using a mouse, a scroll bar to conduct
fine adjustment of the Z-directional driving by use of a mouse, a
reset icon to restore the globe position in the X, Y, Z directions
to a central point, a combo box to select a speed to inch the probe
in the X, Y, Z directions, a combo box to select a step length to
inch the probe in the X, Y, Z directions, and a combo box to select
a speed to sequentially move the probe in the X, Y, Z directions. A
globe position display GUI field 211 includes a display field of a
current positional state of each probe.
Although the respective GUI fields are arranged on the GUI in FIG.
2, the GUI fields may be replaced with each other to help the user
easily conduct observation and operation described above.
Next, referring to FIGS. 3A to 3D, description will be given of a
display example, on the SEM.cndot.probe.cndot.stage control GUI
201, of an SEM image and probes selected as above. The example of
FIG. 3A shows a state to control probe no. 1. The SEM and GUI
display conditions are designated as 10000 (10 k) for the SEM
display magnification ratio and 0 degree (0.degree.) for the
rotation angle. Probes no. 1 and no. 2 are moved to approach an SEM
display object. Under the conditions, a probe no. 1 302, probe no.
2 303, a SEM display object 304, and a no. 1 display GUI field 305
are displayed in the SEM display screen (GUI) 301 (corresponding to
the SEM/CAD data display field 203 of FIG. 2). A selection control
dial GUI field 307 of a probe selection GUI field 306 indicates a
position of probe no. 1, and a magnification ratio display GUI
field 308 displays 10000, i.e., 10 k. In a rotation display GUI
field 309, a rotation adjusting knob GUI field 310 and a rotation
angle display GUI field 311 indicates 0 degree (0.degree.). The no.
1 display GUI field 305 indicates that probe no. 1 is a probe
selected by a probe selecting unit. This means that probe no. 1 is
a controllable probe to be moved toward the SEM display object (SEM
image) or to be retracted to apart therefrom. This may be conducted
in another method, for example, such selected probe is visually
indicated or is indicated using a particular color.
Next, FIG. 3B shows an example of a state of the GUI 301 when the
state of FIG. 3A is changed to control probe no. 2. The SEM display
screen displays a probe no. 2 display GUI field 313 in place of the
no. 1 display GUI field 305. The selection dial GUI field 307 of
the probe selection GUI field 306 indicates a position 313 of probe
no. 2.
FIG. 3C shows an example of a state of the GUI 301 when the state
or FIG. 3B is changed to set the SEM display magnification ratio to
5000 (5 k). As a result of the magnification ratio change, the SEM
display screen displays a wider-range image such that the probe no.
1 302, the probe no. 2 302, the probe no. 2 display GUI field 313,
and the SEM display object 304 are displayed with a magnification
ratio of 5000. Simultaneously, the magnification ratio display GUI
field 308 is changed to indicate 5000, i.e., 5 k.
FIG. 3D shows an example of a state of the GUI 301 when the state
or FIG. 3C is changed to rotate the display image 90.degree. by use
of the display rotation unit. When the user operates the rotation
adjust knob GUI field 312 to move the knob to a position of
90.degree. (319 in FIG. 3D), the value of the rotation angle
display GUI field 311b is changed to indicate 90.degree. (320 in
FIG. 3D). The SEM display screen is also rotated 90.degree. in the
direction of the arrow (321). Probe no. 1 302, probe no. 2 303, the
probe no. 2 display GUI field 313, and the SEM display object 304
are displayed at respective positions rotated 90.degree..
As above, there is provided a defect inspecting apparatus including
a probe image processing unit to display a plurality of probes on
the display unit, a unit to select, from the plural probes
displayed on the display unit, a probe to be operated; and a unit
to simultaneously display information indicating that the probe
thus selected is an operable probe and a non-selected probe at the
same time.
FIG. 4 shows a probe control GUI field 401 to control driving of
the mechanical probes 106. The field 401 includes an arrow icon 403
similar to a scroll bar 402 to inch the probe in the X, Y, and Z
directions using a mouse, a GUI display field 404 to display a
quantity of voltage applied to a piezoelectric element to drive the
probe, an arrow icon 405 to step-wise move the probe, an arrow icon
406 to continuously move the probe, a reset icon 407 to restore the
globe position in the X, Y, Z directions to a central point, a
combo box 408 to select a speed to inch the probe in the X, Y, Z
directions, a combo box 409 to select a step length to inch the
probe in the X, Y, Z directions, and a combo box 410 to select a
speed to sequentially move the probe in the X, Y, Z directions. To
cautiously bring the probe into contact with an inspection object,
the GUI field 401 also includes a Z-directional inching scroll bar
411. The bar 411 is used to display a magnified image of the object
at a desired position in a Z-directional inching range, and hence
the control operation can be more precisely conducted.
FIG. 5 shows a GUI field 501 to conduct a changeover of control
between the base stage, the DUT stage, and the image shift. The
field 501 includes icons 502 to conduct selection to respectively
move the base stage, the DUT stage, and the image shift; icons 503
to respectively lock the base stage, the DUT stage, and the image
shift not to move the selected item, and an icon 504 to stop the
control operation of the base stage, the DUT stage, or the image
shift under the control operation.
FIG. 6 shows a GUI field 601 to control the base stage. The field
601 includes an icon 602 to move the main stage 111 to a sample
change position, a measuring position, or a CCD observing position,
icons 106 to move, for example, the mechanical globe 106 to a globe
change position, an icon 604 to turn a feedback function to remove
backlash occurring in the base stage on and off, and a coordinate
input.cndot.display box 605 to input and to display coordinates of
the base stage.
FIG. 7 shows a GUI field 701 to display a current position of each
probe unit. The probe position display GUI field 701 includes a GUI
field 702 to visually indicate a current position in the X
direction of an associated probe unit, a GUI field 703 to visually
indicate a current position in the Y direction of the probe unit, a
GUI field 704 to visually indicate a current position in the Z
direction of the probe unit as well as a GUI field 705 to
numerically indicate a current position in the X direction of the
probe unit, a GUI field 706 to numerically indicate a current
position in the Y direction of the probe unit, a GUI field 707 to
numerically indicate a current position in the Z direction of the
probe unit.
FIG. 8 shows a GUI field 801 to register to a memory the
coordinates respectively of the main stage, the DUT stage, and the
memory shift to move the probe to a position indicated by
information thus registered. The field 801 includes an icon 802 to
register to the memory the coordinate values respectively of the
main stage, the DUT stage, and the memory shift; check boxes 803 to
respectively select information items respectively of the main
stage, the DUT stage, and the memory shift; GUI fields 804 each of
which displays coordinate information registered and/or called by
the operator, a combo box 805 to select and to call the registered
coordinates, an icon 806 to move the main stage, the DUT stage, or
the memory shift to a position of registered coordinates thus
called; and an icon 807 to erase the registered coordinates.
FIGS. 9A to 9C show a GUI field to display (or not to display) CAD
navigation information for a sample of a semiconductor device of
which a surface has been worked to measure electronic
characteristics thereof. As the CAD navigation information, a
sample information image created by a sample information image
processing unit is displayed. The SEM display screen 301 of FIG. 9A
displays plug no. 2 303 selected from a plurality of plugs 902 of
the semiconductor device, together with a probe no. 2 display GUI
field 313. The SEM control GUI field 202 of FIG. 9A includes a GUI
field 903 to designate "display" or "nondisplay" of the CAD
navigation information.
FIG. 9B shows a state in which the AD navigation information is
displayed. When the user clicks an Overlay GUI field 904, CAD
information about a group of plugs 906 is displayed on the SEM
display screen 301 as an overlay image with a magnification ratio
indicated by the SEM display magnification ratio field 905. When
the user clicks the GUI field 904 again in this state, the plug
group field 906 is set to a nondisplay state.
FIG. 9C shows a state to combine the CAD navigation information
with the SEM display image. When the user clicks the Fine Adjust
GUI field 903 in the situation in which the plug group 906 is being
displayed on the SEM display screen 301, the device information is
again aligned with the CAD information to correct discrepancy
between the device plug group 908 of the SEM display and the device
plug group 906 of the CAD information in the display image.
FIG. 10 shows a control GUI field 1001 to retract a probe unit. The
probe unit retraction control GUI field 1001 includes a combo box
1002 to select a probe unit as a control object, an icon 1003 to
retract the probe unit in the X direction (to a position of an
origin in the X direction), an icon 1004 to retract the probe unit
in the Y direction (to a position of an origin in the Y direction),
and an icon 1005 to retract the probe unit in the Z direction (to a
position of an origin in the Z direction); and an icon 1006 to
retract the icon in the X, Y, and Z directions (to a positions of
an origin in the X, Y, and Z directions). Using the combo box 1002
to select a probe unit, the user can select any possible
combination of the probe units.
The defect inspecting apparatus includes a unit to retract a probe
unit to an origin of each coordinate axis of the probe unit, a unit
to retract a probe unit to a position indicated by the origins
respectively of the coordinate axes of the probe unit, and a
function to simultaneously retract a plurality of probe units to
the positions of the origins respectively of the coordinate axes.
The apparatus displays switches to operate the units on the display
screen.
FIG. 11 shows a sample stage control GUI field 1101 to control the
GUT stage. The field 1101 includes a cross cursor 1102 to indicate
current positions in the X, Y, and Z directions of the DUT stage,
arrow icons 1103 to move the DUT stage in the X, Y, and Z
directions, a combo box 1104 to select a length of movement in the
X and Y directions of the DUT stage, a coordinate
input.cndot.display GUI field 1105 to input and to display
coordinates in the X, Y, and Z directions of the DUT stage, a reset
button 1106 to restore the DUT stage to the origin in the X and Y
directions, a GUI field 1107 to indicate a current position in the
Z direction of the DUT stage, an icon 1108 to move the DUT stage to
a sample measurement standard position in the Z direction, an icon
1109 to move the DUT stage to a lower-most position in the Z
direction, an icon 1110 to move the DUT stage a long distance in
the Z direction, a combo box 1111 to select the large distance
movement in the Z direction, an icon 1112 to inch the DUT stage in
the Z direction, and a combo box 1113 to select the inching
movement in the Z direction.
FIGS. 12A to 12C show operation to measure a relative distance
between a probe and a target object to automatically bring the
probe into contact with the object. The defect inspecting apparatus
includes a unit to set a target to a desired section or position of
a sample information image and a unit to bring a probe selected for
the target as above into contact with the target. The apparatus
also includes a unit to calculate distance between a tip end of the
probe and the target before the probe is brought into contact with
the target and a unit to make the display unit display the distance
thus calculated. FIG. 12A shows on the SEM display screen 301 a
plurality of plugs 1202 of the semiconductor device, a plug 1203 as
a target object, a plug no. 2 probe 303 to be brought into contact
with the target, and a control GUI field 1205 to automatically lead
contact between the probe and the target object.
FIG. 12B shows a state to process information to lead contact
between the probe and the target object. When the user clicks a
target object confirmation GUI field 1206 of the control GUI field
1205, a cursor 1207 appears on the SEM display screen 301. The user
clicks two positions, i.e., the target object and a tip end of the
probe to be brought into contact with the target object. The
clicking of the positions may be in an order other than the order
described above. The defect inspecting apparatus then executes SEM
autofocus and auto-stigma processing, displays distance between the
two points on the screen and a relative distance between the two
clicked positions using SEM work distance in three dimensions x, y,
and z; displays on the SEM display screen distances in the x, y,
and z directions indicated in the relative distance display GUI
field 1208, and stores the information in a memory of the control
PC.
FIG. 12C shows a state to automatically lead contact between a
probe and a target object. When the user clicks an automatic probe
contact GUI field 1209, the defect inspecting apparatus controls
the probe according to the information obtained through the
operation shown in FIG. 12B to bring the probe into contact (1210)
with the target. In the situation, to secure the contact between
the probe and the target, the operation may be carried out by
conducting self-correction of the information using an image
processing technique.
As above, the defect inspecting apparatus of the embodiment
includes a unit to display probes on an obtained image together
with information indicating that the probes are in the controllable
state.
The apparatus also includes a unit to make the probe display follow
a rotation of the display screen by the rotation function and a
unit to magnify or to minimize, in response to a change in the
display magnification ratio of the electrooptical system, the
contour of the probe display according to the display magnification
ratio.
The defect inspecting apparatus can display an instruction to the
probe unit moving unit on the display screen.
The apparatus can display on and can conceal from the display
screen a display screen to select an operation range for the probe
unit moving.
The apparatus also includes a changeover switch to change a control
state of the probe unit and can display the changeover switch on
the display screen.
The defect inspecting apparatus includes a changeover switch to
change a control state of the sample stage, the base stage, and the
charged-particle beam and can display the changeover switch on the
display screen.
The apparatus includes, for a method of aligning the base stage,
selection switches to move the sample respectively to the electric
characteristic measuring position, the sample change position, and
the probe holder change position and can display the switches on
the display screen.
The apparatus can display, for the selection switches on the
display screen, the position and the state of the base stage
selected by the user in mutually different colors. This makes the
user visually confirm the current position and state of the base
stage.
The defect inspecting apparatus includes a unit to visually and
numerically display positions of the plural probe units on the
display screen.
The apparatus includes a storage unit to store positional
information of the sample stage, the base stage, and the
charged-particle beam; a unit to display the information on the
display screen, and a selection switch to move the positions of the
sample stage, the base stage, and the charged-particle beam. The
apparatus includes the selection switch on the display screen.
The apparatus can display the obtained image and the sample
information on the display screen. The apparatus can display the
image and the information in an overlay image. The apparatus can
display a display.cndot.nondisplay changeover switch for the
display of the image and the information. The apparatus can display
the changeover switch on the display screen.
The defect inspecting apparatus includes a unit to retract a probe
unit to an origin of each of the coordinate axes of the probe unit,
a unit to retract a probe unit to an origin of the coordinate axes
of the probe unit, and a unit to retract a plurality of probe units
to the units to origins respectively of the coordinate axes of the
probe units. The apparatus can display switches to operate these
units on the display screen.
The apparatus includes a unit to move the sample stage according to
sample information to display a desired position of the sample
information and a unit to move, in association therewith, the probe
unit to move a probe to the desired position of the sample
information.
The defect inspecting apparatus includes a unit to automatically
bring the probe attached to the probe unit into contact with a
target object on the sample by use of an autofocus unit and an
auto-stigma unit.
The apparatus also includes a function to retract the sample stage
in a direction to apart from the probe and a function to move or to
inch the sample stage a fine length such that the sample approaches
the probe or removes from the probe. The apparatus can display
switches to conduct these functions.
For a defect inspecting apparatus in which probes are combined with
a charged-particle beam unit, it is proposed that graphic user
interfaces (GUI) to control a plurality of probes disposed in a
complex arrangement are disposed on the screen in which the SEM
image display screen is displayed. According to the present
invention, operability and usability of the apparatus are
remarkably increased to control the charged-particle beam unit.
It should be further understood by those skilled in the art that
although the foregoing description has been made on embodiments of
the invention, the invention is not limited thereto and various
changes and modifications may be made without departing from the
spirit of the invention and the scope of the appended claims.
* * * * *